Circuit-timing device.



W. MEYER. cmc'un TIMING DEVICE. APPLICATION FILED FEB. 15. 1915.

Patented Mar. 14, 1916.

mm 3 \w IHVEHW; William Me a Fl EIIHE 5 dll WTLLIAM MEYER, CHICAGO, ILLINOIS.

CIRCUIT-TIMING DEVICE.

Specification of Letters Patent.

Patented T133111 1 1, 1216,

Application filed February 15, 1915. Serial No. 8,214.

To all whom it may concern:

Be it known that 1, WILLIAM MEYER, a citizen or" the United States, residing at Chicago, in the county of Cook and State or Illinois, have invented a certain new and useful improvement in Circuit-Timing Devices, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

The present invention relates to a circuittiming device and is especially adapted to control the time of the energization of an X-ray bulb, or the like, in order to limit the time of exposure of a patient to the X-ray treatment.

The object or" the present invention is to provide an improvedtiming-device for electrical circuits, or the like.

The accompanying drawing, which forms a part of this specification, illustrates diagramatically an embodiment of my invention.

The apparatus illustrated in the figure consists essentially of a switch 1 in the circuit oi the primary or" the X-ray device, an electro-magnet 2 controlling the switch 1, a timecontrolled element 3 and a connection between the electr c-magnet 2 and the time-controlled element, and acontrolling circuit having an automatic switch 5 and a manual switch 6 for properly controlling the circuit, will he described later.

The switch 1 comprises a cup 7, having mercury the bottom thereof, and a plunger 8, which is connected to the other side or" the primary X-ray, circuit. The plunger 8 is insulated from but mounted upon the core 9 of the solenoid 2 and is adapted to be moved into engagement \vith the mercury in the bottom of the cup 7 when the solenoid 2 is energized.

The time-controlled element 3 includes a dash-pot .10 having a plunger 11 slidably mounted therein. The plunger 11 bears a stem 12, which is provided with suitable graduations, as indicated in the drawing. A handle 13 is provided for raising this plunger to any desired position in order to cause the graduations to register with the indicating" brake. The indicating brake comprises a sliding bar 14 which engages in notches in the stem 12. The .bar 14, is held against the stem 12 by the tension of the it is necessary to maintain a distance of at least a of an inch between the plunger electrode 8 and the surface of the mercury in the cup 7, an appreciable time elapses after the automatic timing device starts to work. before the main circuit is closed. l here the time of exposure is to be as short as onetenth of a second, this lost time forms a. very appreciable percentage. in order to overcome this 1 have provided a lost motion coupling which will consume an equal amount of time in causing release of the brake, so-that the timing can be made with any desired degree of accuracy. To this purpose, the short arm of the lever 23, which is pivoted at 15 and which connect the plunger 9 with the brake 14, plays in a slot or notch 24. The other end of the brake lever 23 is connected to the plunger 9 of the solenoid 2. A spring, not shown, normally holds the plunger 9 in raised position. The stem 12 bears a projection 16, which, as shown in the drawing, consists of collar surrounding the plunger, which collar engages a spring 1? forming a part of the automatic switch 5.

When the parts are in the posit on shown in the drawing, the controlling circuit l connects the solenoid 2 with the automatic switch 5 through the battery and through the normally open controlling swZtch A switch 19 is provided for cutting out the automatic switch 5 if it is desired to close the primary circuit or" the X-ray apparatus for any considerable length of'time. W hen the switch 19 is thrown upon its alternate contact the automatic switch 5 will be included in the circuit, and the automatic timing element 3 will then become operative to open the circuit of the X-ray primary at the end of any predetermined interval of time.

The operation of the device is as follows: it it is desired to use the automatic timing control the switch 19 is placed upon the alternate current contact A. The stem 12 is then raised by means of the handle 13 until the desired graduation comes opposite the end of the brake 14. This stem 12 may be graduated in any preferred manner. It is shown in the drawing as graduated in Q2 of a second period. The stem 12 is held in raised position by the brake 1 1 until the the electrode 8 into the mercury cup 7 to close the primary circuit of the X-ray device. At the same time the brake lever 23 throws off the brake 14 and releases the stem 12 and this stem is then free to drop. At the expiration of the predetermined time the collar 16 will engage the spring 17 and disengage it from the stationary contact 18. The controlling circuit 4 is thereby broken and the plunger 9 of the solenoid 2 is raised, breaking the contact of the primary of the X-raydevice at the mercury cup 7. The dash-pct 10 is provided with a valve or vent, not shown in the drawing, the degree of opening of which may be controlled by r0 tating the cap 21, secured to the bottom of the dashpot 10. \Vhen the graduation 1 shown in the drawing at the bottom of the dashpot 10 is brought opposite the zero position on the dashpot, the time required by the plunger to drop the full length of the stroke of the dashpot is one second. If the setting of the cap 21 be shifted from this position, the time of dropping of the plunger 12 will be correspondingly lengthened or shortened. If it is desired to close the X-ray circuit for a period longer than that covered by the dropping of the plunger, the switch 19 may be moved to the position u shown in the drawing, in which the automatic switch 5 will be cut out of the controlling circuit, and the switch 6 will hold the controlling circuit, and thereby the main I circuit, closed as long as it is depressed.

It is to be noted that when the automatic switch 5 is in circuit the key 6 is depressed until the circuit has been broken at the,

' switch points 17-18 by means of the time terial.

I consider the provision of means to delay the operation of the timing device until the instant that the contacts are changing the circuit conditions, to be broadly'new.

It is obvious that the same principle of operation may be involved in controlling a,

normally closed circuit as well as the open circuit which I have described and illus trated. It is also to be understood that my invention contemplates the employment of suitable adjustments for the various elements.

The above-described mechanism embodies the principles of cheapness, simplicity and reliability, and, although various changes may be made which will be apparent to those skilled in the art, I desire that these changes or modifications be considered as coming within the spirit and scope of my invention as defined by the appended claims. What I claim as new and desire to secure by Letters Patent of the United States is: 1. In a device of the class described, a normally-open working circuit including a plunger and a mercury cup, an electro-magnet controlling said plunger, a control-circuit for said electro-magnet, contacts in said control circuit, a timing element adapted to open said contacts to break said control circuit, a brake normally restraining the action of said timing element, a connection between said brake and said magnet, said connection having lost mction to cause the plunger and with the release of the brake, and a switch for closing said control circuit.

2. In a circuit-timing device, a working circuit having a pair of contacts, electromagnetically controlled means for moving one of said contacts to change the condition of the circuit therethrough, a control circuit for said means, a manually operated switch for controlling said circuit, an automatic timing device for removing control of said means from said controlling circuit after a predetermined period of time, a connection between the electro-magnetic means and said timing means, said connection comprising means for delaying the startingof said timing device until the instant of change of circuit condition through said working circuit contacts.

A circuit-timing device comprising a normally open working, circuit having a movable contact to close said circuit, an electro-magnet'controlling said movable contact, a control circuit for said electro-magnet, contacts in said control circuit,a timing elecontact into engagement; with said other contact, and a timing element having means for determining and indicating the time during which said contacts are closed, said first means and said timing element having a loose coupling between them to allow the gap between said contacts to be closed at the instant that the timing device begins to operate.

5. In combination, a timing device, a brake normally restraining the action of said timing device, a pair of normally separated contacts, one of said contacts being movable into engagement with said other contact, and common means for releasing said brake and for moving said movable contact into engagement with theother contact, said common means and said brake having a loose coupling between them to allow movement of said movable contact prior to release of said brake.

6. In combination a pair of normally sep-' arated contacts, one of said contacts being movable, means for moving said movable contact into engagement with said other contact, timing means governing said first means, and a loose coupling between said contact moving means and said timing means governed by said first means to institute the operation of said timing element to allow the gap between said contacts to be closed as the timing device begins to operate.

7. In combination a pair of normally separated contacts, one of said contacts being movable, a solenoid having a plunger for moving said movable contact into engagement with said other contact, a timing device for shutting off the current in said solenoid, means connected tosaid plunger to start said timing device after the plunger begins tomove to allow the gap between said contacts to be closed before the timing device begins to operate.

8. In combination a pair of contacts, said contacts comprising a movable plunger of resilient metal, and a stationary mass of non-resilient metal, an electro-magnet having a movable magnetic element for operating said plunger, a circuit for said electromagnet, a timing device which operates after a predetermined period of time to open said circuit, a lever connected between said plunger and the timing device for starting said timing device.

9. In combination, a solenoid having a plunger, a cup, a conducting liquid in said cup, said plunger and said liquid forming a pair of normally open contacts for a working circuit, a control circuit for said solenoid, a timing device which operates after a predetermined period of time to open said control circuit, a brake for said timing de-' vice and a lever connected between said plunger and said brake to start the operation of the timing device.

10. In combination a solenoid having a plunger, a contact mounted on said plunger, amercury cup cooperating with said contact, a dashpot having a vertical stem, a horizontal slide having spring means to cause said slide to engage said stem, a bell crank lever having one arm attached to said plunger and the other arm playing in a notch or slot in said slide, a circuit for said solenoid and contacts in said circuit controlled by said dashpot.

11. In a device of the class described, the combination of a working circuit having a pair of normally opened contacts, said contacts comprising a vertical plunger and a mercury cup below the same, an electromagnet having a movable magnetic element connected to'said vertical plunger to operate the same, a control circuit for said electromagnet, a manual switch for said control circuit, an automatic time controlled element, a switch governed by said time controlled element, and a lever connected between said movable magnetic element and said time concontrolled element, to start the operation of said time controlled element.

In witness whereof, I- hereunto subscribe my name this 11th day of February, A. D. 1915.

WILLIAM MEYER.

Witnesses:

JOHN A. DIENNER, LESLIE IV. FRICKB. 

